ZDI-07-026: Microsoft Excel BIFF File Format Named Graph Record Parsing
            Stack Overflow Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-07-026.html
May  8, 2007

-- CVE ID:
CVE-2007-0215

-- Affected Vendor:
Microsoft

-- Affected Products:
Office Excel 2000
Office Excel 2002
Office Excel 2003

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability since May  8, 2007 by Digital Vaccine protection
filter ID 5330. For further product information on the TippingPoint IPS:

    http://www.tippingpoint.com 

-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Microsoft Office Excel. Exploitation
requires that the attacker coerce the target into opening a malicious
.XLS file.

The specific flaw exists within the parsing of the BIFF file format
used by Microsoft Excel. During the processing of a malformed Named
Graph record, user-supplied data may be copied to the stack unchecked
thereby leading to an exploitable stack-based buffer overflow.

-- Vendor Response:
Microsoft has issued an update to correct this vulnerability. More
details can be found at:

    http://www.microsoft.com/technet/security/bulletin/ms07-023.mspx

-- Disclosure Timeline:
2006.11.16 - Vulnerability reported to vendor
2007.05.08 - Digital Vaccine released to TippingPoint customers
2007.05.08 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by Manuel Santamarina Suarez.

-- About the Zero Day Initiative (ZDI):
Established by TippingPoint, a division of 3Com, The Zero Day Initiative
(ZDI) represents a best-of-breed model for rewarding security
researchers for responsibly disclosing discovered vulnerabilities.

Researchers interested in getting paid for their security research
through the ZDI can find more information and sign-up at:

    http://www.zerodayinitiative.com

The ZDI is unique in how the acquired vulnerability information is used.
3Com does not re-sell the vulnerability details or any exploit code.
Instead, upon notifying the affected product vendor, 3Com provides its
customers with zero day protection through its intrusion prevention
technology. Explicit details regarding the specifics of the
vulnerability are not exposed to any parties until an official vendor
patch is publicly available. Furthermore, with the altruistic aim of
helping to secure a broader user base, 3Com provides this vulnerability
information confidentially to security vendors (including competitors)
who have a vulnerability protection or mitigation product.